1. Field of the Invention
The present invention relates to an oxygen breathing apparatus used to deliver oxygen to a person having lungs of limited capacity due to lung damage which require supplemental oxygen to assist in everyday life, wherein oxygen is supplied from an oxygen supply source such as an oxygen concentrator, a compressed oxygen supply tank and the like to nostrils of the person through a pair of cannulas (i.e., medical tubular members). More particularly, the present invention relates to such an oxygen breathing apparatus, which is integrally formed with a spectacle kit (i.e., eye-glasses) to assume a spectacle shape in appearance, and is substantially free from any deformation of a common joint portion (described later) of the spectacle kit.
2. Description of the Related Art
Heretofore, it has been known to provide a spectacle-shaped oxygen breathing apparatus, which is excellent in appearance and capable of steadily supplying oxygen to a person wearing the breathing apparatus without any fear that a pair of cannulas having been inserted into nostrils of the person drop out of the nostrils in use.
Such a conventional spectacle-shaped oxygen breathing apparatus is shown in FIGS. 8 and 9. As is clear from these drawings, the spectacle kit of the conventional breathing apparatus has some or all of its frame members constructed of tubular members to permit its temple members 2 and its corresponding end piece members 3 to air-communicate with each other. As shown in FIG. 8, as to the spectacle kit, an opening end portion 21 of the temple member 2 is hermetically connected with a small-diameter cannula 4 which extends from an oxygen supply source (not shown). On the other hand, the end piece member 3 has its opening end portion 31 hermetically connected with a nostril cannula 5. The breathing apparatus is easy in wearing, and excellent in appearance when worn by a person. Further, in the spectacle kit of the apparatus, as shown in FIG. 9, the temple members 2 are connected with the end piece members 3 through hinged joints 6. This makes it possible for the person wearing the breathing apparatus to fold the apparatus during non-use thereof. The thus folded apparatus is capable of reducing its size to realize easy storage of the apparatus. This is very advantageous to the person using the breathing apparatus.
In the hinged joints 6 of the spectacle kit, as is clear from FIG. 9, the tubular endpiece member 3 is rotatably connected with the corresponding tubular temple members 3. During non-use of the breathing apparatus, when the temple members 2 of the spectacle kit are unfolded, a sleeve-like insertion convex portion 33 of each endpiece member 3 is hermetically inserted into an open end portion 22 of the corresponding temple member 2, which enables oxygen to be transferred from the temple member 2 to the endpiece member 3 of the spectacle kit without any leakage of oxygen.
However, the conventional breathing apparatus suffers from the following problems, which will be now described in detail.
It is necessary for the breathing apparatus to supply oxygen, at a relatively small constant rate, from the oxygen supply source (not shown) to the nostril cannulas 5. Due to this, each of the endpiece members 3 and the temple members 2 is constructed from a small-diameter tubular member, a diameter of which is substantially equal to that of the small-diameter cannula 4. Further, in order to keep excellencies of the breathing apparatus in appearance, weight and fittingness, the small-diameter cannula 4 is constructed of a tubular member with the thinnest possible wall thickness.
Due to this, the open end portion 22 of the temple member 2, into which the sleeve-like convex portion 33 of the endpiece member 3 is hermetically inserted, is also thin in wall thickness. Consequently, in inserting the sleeve-like convex portion 33 of the endpiece member 3 into the open end portion 22 of the temple member 2, the sleeve-like convex portion 33 of the endpiece member 3 is brought into frictional contact with the open end portion 22 of the temple member 2. When such frictional contact is repeatedly performed in use, a stop screw 61 of the hinged joint 6, through which the endpiece member 3 is rotatably connected with the temple member 2, is often loosened. When the stop screw 61 is loosened, as is clear from FIG. 9, the open end portion 22 of the temple member 2 is flared outwardly to cause oxygen leakage. There is also a fear that the sleeve-like convex portion 33 of the endpiece member 3 is deformed or battered down to prevent passage of oxygen through the portion 33. The above troubles in passage of oxygen make it impossible for the breathing apparatus to supply oxygen to the person at a necessary rate prescribed by a doctor in charge, which often leads to the person's anoxia such as cyanosis and like damages.